Aid system, in particular for use in ice rescue

ABSTRACT

An aid system includes a base element, an expandable tube arrangement including at least one tube portion to form a tube run extending between a base portion assigned to the base element and a head portion at a free end of the tube run, and a pressurized fluid system that fills the tube portion with pressurized fluid, wherein (i) the tube portion is guided between a tube store and the head portion by a tube guiding device with a tube guiding opening constricting a cross section of the tube portion, and (ii) at least one pressurized fluid inlet leading into the interior of the tube portion in the region of the head portion.

RELATED APPLICATIONS

This application claims priority of German Patent Application No. 10 2009 054094.6, filed Nov. 12, 2009, and European Patent Application No. 10013739.7, filed Oct. 18, 2010, herein incorporated by reference.

TECHNICAL FIELD

This disclosure relates to an aid system, in particular for use as an ice rescue system in ice rescue.

BACKGROUND

During sustained periods of cold weather, small ponds, lakes or not very fast flowing streams and rivers may partially or completely freeze over. Children in particular are captivated by such icy surfaces and enticed to create slides and engage in sporting activities such as ice skating, ice hockey or curling. Adults, too, often cannot resist the temptation to go onto the frozen-over icy surfaces, even if they have not been declared open. In these times, ice rescue becomes particularly important, since insufficient load-bearing capacity of the ice or deceptive thicknesses of ice can easily lead to accidents in which people fall through the ice.

A fall into cold water can cause heart failure, and the person who has fallen in can no longer help him/herself. Even if this is not the case, generally only little time remains for rescue, since a person can usually only survive in cold water for 15 to 20 minutes at most. Passers-by generally cannot provide any help because of fear or uncertainty, and so the only way that victims will be rescued is by permanent water rescue stations, ice guards or rapidly deployed ice rescue teams or the fire service.

Ice rescue without any aids is difficult and dangerous. Therefore, suitable rescue equipment is used wherever possible. Suitable in principle as rescue equipment for ice rescue are all items that distribute the weight of the rescuers and the victim over as large an area as possible on the ice and are capable of bridging the distance from a safe place to the victim. Bars, ladders and/or boards are often used as aids. There have also been many proposals for aid systems that are specifically adapted to the requirements of ice rescue.

WO 03/097438 A2 discloses a motor-driven hydroplane for ice rescue. It has a catamaran-like main body, comprising at least two parallel inflatable tubes placed at a mutual distance from one another, and a base which is located between the tubes and on which an air propeller propulsion device is fixed. Such special vehicles are relatively complex in their construction and are accordingly expensive, and are generally only considered for deployment at highly frequented expanses of water.

U.S. Pat. No. 4,047,257 discloses a lifesaving apparatus constructed essentially like a snow fence that can be rolled up. Fastened to one end is a base part for fixing to the shore of an expanse of water and fastened to the other end is an essentially cylindrical flotation device, which is produced from rigid foam and serves as a support for the wound up run of fence and serves in the unrolled state as an aid for rescuing the victim.

U.S. Pat. No. 4,990,114 discloses an ice rescue system with a portable base element to which there is attached an inflatable tube arrangement, which has two tube portions arranged at a mutual distance from one another to form a tube run which extends between a base portion assigned to the base element and a head portion at the free end of the tube run. A compressed gas system for filling the tube portions with compressed gas has two compressed air cylinders attached to the base element and connected to compressed gas inlets, which are located at the ends of the tube portions lying on the base element. The base element has a pocket-like container provided with carrying handles and in the interior of which the tube arrangement is stored in a folded-up state when the aid system is not required. For deployment, the container is placed on the shore of the frozen-over expanse of water, lined up with the victim and opened. Filling the tube portions with compressed air causes the tube portions to be quickly filled with air from the side of the base element, and the tube run unfolds and, once filling has been completed, its end portion reaches as far as the victim. Attached to the head portion are anchoring lines, which can be grabbed by rescuers standing on the shore to line up the head portion more precisely with the victim by pulling sideways. A rescuer can then use the extended tube run as a rescue route to reach the victim and pull him/her out of the water. It is described that such aid systems are available in different extendable lengths, for example with a length in the inflated state of 50 feet, 100 feet or 150 feet.

U.S. Pat. No. 4,106,149 discloses an inflatable flotation bridge. The inflatable bridge can be rolled up or folded together in the non-inflated state. It has two inflatable tube portions arranged at a mutual distance which can be filled with compressed air from the base portion lying on the outside in the rolled-up state to unroll the bridge. Arranged at certain intervals between the tube portions are relatively rigid, but elastic pressure distributing elements, which also serve as spacers for the tube portions.

It could therefore be helpful to provide an aid system which can be used in particular as an ice rescue system in ice rescue, is of a simple construction, operates reliably in a wide variety of rescue situations and, in particular, can be used with greatly differing useful lengths.

SUMMARY

We provide an aid system including a base element, an expandable tube arrangement including at least one tube portion to for a tube run extending between a base portion assigned to the base element and a head portion at a free end of the tube run, and a pressurized fluid system that fills the tube portion with pressurized fluid, wherein (i) the tube portion is guided between a tube store and the head portion by a tube guiding device with a tube guiding opening constricting a cross section of the tube portion, and (ii) at least one pressurized fluid inlet leading into the interior of the tube portion in the region of the head portion.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a perspective schematic representation of an ice rescue system in use.

FIG. 2 shows a schematic front view of a transportable aid system which can be used in particular for ice rescue.

FIG. 3 shows schematic representations for explaining the functional principle when the tube arrangement is extended, FIG. 3A showing the tube arrangement in the largely rolled-together state and FIG. 3B showing the tube arrangement in a partially extended state.

FIG. 4 shows a schematic side view of a tube arrangement with a carriage that can be moved on it in the longitudinal direction.

FIG. 5 shows a view of a tube arrangement in the longitudinal direction of the tube arrangement with a carriage running on the tube portions.

DETAILED DESCRIPTION

An aid system of the generic type is distinguished by the feature that the tube portion intended for forming a tube run is guided between a tube store and the head portion at the free end of the tube run by a tube guiding device with a tube guiding opening constricting the cross section of the tube portion and by the feature that at least one pressurized fluid inlet leading into the interior of the tube portion is provided in the region of the head portion.

This achieves the effect that the tube portion is filled from the front end or from the head portion of the tube run when pressurized fluid is introduced through the pressurized fluid inlet. The pressurized fluid introduced then fills the tube portion between the head portion and the region of the tube guiding device, which constricts the cross section of the tube portion in the region of the tube guiding opening and in the most favorable case presses it together or seals it off in a largely fluid-tight manner. This allows a high fluid pressure to build up in the tube portion between the head portion and the tube guiding device, and the tube portion is filled under pressure until taut and stabilizes the extended length of the tube run as largely flexurally rigid elements. The more pressurized fluid is introduced, the greater length of tube is drawn from the tube store and moved through the tube guiding opening, to be expanded on the far side of the tube guiding opening and contribute to the overall length of the expanded tube run. The usable extended length of the tube run, measured between the tube guiding device or the tube guiding opening and the head portion, can therefore be regulated steplessly to any desired values up to a maximum extended length by controlling the supply of pressurized fluid, the tube portion being filled until taut, and the tube run thereby stabilized, in the case of every extended length. This is a major difference in comparison with conventional systems with inflatable tube arrangements, which only achieve the stabilized, fully inflated state required for use when the entire tube arrangement has expanded to its maximum length.

The tube run may have a single tube portion. The cross section thereof in the expanded state should be relatively flat, that is to say have a relatively small height in comparison with the width so that a tube run is formed when it expands. The height may be, for example, at most 20% of the width or at most 10% of the width. For this purpose, it may be provided that longitudinally and/or transversely running webs or other connecting elements are stitched or in some other way incorporated within a flexible fluid-tight tube enclosure and connect the opposite inner sides of the tube enclosure to one another, and so expansion in the direction of the webs is limited and a round cross section is not obtained, but rather a flat cross section.

Preferably, the tube arrangement has at least two tube portions arranged at a mutual distance from one another. In particular, precisely two tube portions may be provided. These may laterally delimit the tube run. If a number of separate tube portions are provided, the individual tube portions can be constructed in a particularly simple and robust manner. They can each have a round cross section in the expanded state.

There may also be more than two tube portions provided, running at a distance from one another or close to one another, for example in the manner of an air mattress. There is then a lateral distance in particular between the outer tube portions laterally delimiting the tube run, it being possible for one or more further tube portions to lie between these outer portions.

In the case of a particularly simple structural design, the tube guiding device may have one or more fixed elements, for example, in the form of rods or pipes, which delimit the tube guiding opening or contribute to the formation of a tube guiding opening constricting the cross section of the tube.

A considerable improvement in the function is obtained in the case of a development by the feature that the tube guiding device has at least one pair of oppositely rotatable rollers, which delimit a gap serving as a tube guiding opening for the tube portion to be guided through. With suitable setting of the gap width, the tube portion can be largely sealed off in the region of the gap (serving as a tube guiding opening) by the normally rubberized inner surfaces of the tube portion being pressed against one another by the rollers in such a way that virtually no pressurized fluid can pass from the already expanded parts of the tube portion to the tube entry side at the end where the tube store is located. As a result, a tube portion can be filled until particularly taut and have a stabilizing effect on the tube arrangement. On the other hand, the rollers make it easier for the tube run to be extended quickly to the desired length, since virtually only rolling resistances have to be overcome when extending the length of the tube run.

In some examples, the rollers have parallel axes of rotation and are mounted on the base element. When there are two (or more) tube portions arranged at a mutual distance from one another, a dedicated pair of oppositely rotatable rollers may be provided for each tube portion. With a sufficiently great width of the rollers, a single pair of rollers or rolls may also be sufficient to form a wide gap through which two (or more) tube portions can be guided with a distance between them.

A setting device for changing the axial distance between the rollers is preferably provided. For this purpose, for example, the bearing for one of the rollers of a pair may be mounted in a bearing device such that it can be displaced perpendicularly in relation to the axis of rotation of the rollers and can be fixed in various displacement positions. With the aid of the setting device, an optimum gap width can be set for the phase of the expansion of the tube arrangement, offering a good compromise between sealing on the one hand and low rolling resistance on the other hand. When the tube arrangement is to be brought back again after completion of the deployment, the distance between the axes may be increased to permit easier withdrawal in the direction of the tube store.

The tube store with one or more non-expanded, flat tube portions is preferably in a compact form to facilitate easy transportation of large lengths of tube. In the tube store, tube portions may, for example, be rolled up or multiply folded in a tube pack. At least one tube storing roller for taking up the tube store is preferably provided on a tube entry side of the tube guiding device. In a tube storing roller, relatively great lengths of tube can be stored over long periods of time without any kinks, and consequently in good condition, so that they are operational at any time. When the tube run is expanded, not yet expanded tube portions can then be drawn off from the tube storing roller and moved through the tube guiding opening by the lengthening tube run.

When there are two or more tube portions, a dedicated tube storing roller is preferably provided for each of the tube portions and the tube storing rollers are rotatably mounted on the base part in such a way that there is an intermediate space between the tube storing rollers. This space may correspond essentially to the distance that there also is between the tube portions that have expanded and stabilize the tube run when the tube run is extended. As a result, unrolling is possible without any unnecessary force being applied to the tube portions and without the risk of entanglement.

Preferably, the aid system is operated with compressed gas, in particular with compressed air. In these cases, the pressurized fluid system is a compressed gas system. Expanded, inflated tube portions can then be lightweight, and possibly buoyant, which may be advantageous particularly for deployments in the course of ice rescue or water rescue in general. However, other flowable media, in particular liquid such as water or water-containing liquids or else oily liquids, may possibly also be used for expanding tube portions of the tube run. Expansion by water pressure may be advantageous, for example, whenever the aid device is fitted on a vehicle provided with water pumps, for example, a fire service vehicle or a technical emergency service vehicle.

There are various possibilities for the supply of pressurized fluid to the pressurized fluid inlet on the head portion. If compressed gas is used, it is possible, for example, to provide on the head part a holder for one or more compressed gas cylinders connected via a short line to the compressed gas connection and then travel along with the head part when the tube run is extended.

The pressurized fluid system preferably has at least one flexible pressurized fluid line, which leads from the base part to the pressurized fluid inlet on the head portion and, as the tube run extends, the length of which can likewise increase in a manner corresponding to the increasing length. The source for the pressurized fluid (for example, compressed gas cylinder, compressor, water pump) may then be provided near or on the base part.

In the case of a compressed gas system, a mount for receiving at least one exchangeable compressed gas container, in particular a compressed gas cylinder, may be provided on the base part, and so the compressed gas cylinder can be transported together with the base part.

Compressed gas cylinders, as are also used in breathing apparatus for the fire service or by divers, come into consideration, for example, as compressed gas containers. Such compressed gas cylinders are regularly tested for functional reliability, and the aid system can be kept ready for use at any time even after relatively long periods of not being used. Compressed air is particularly easily available, but in principle other compressible gases or gas mixtures may also be used.

In particular in the case of larger aid systems, possibly permanently installed or fitted to vehicles, and/or in the case of such aid systems in which maximum speed of inflation is not necessarily important during deployment, the use of a compressor is also conceivable as a compressed gas source.

When there are two tube portions arranged at a mutual distance from one another, a suitable spacer may be used to keep the tube portions leading to the head portion at a mutual distance suitable for use in the region of the head portion, which in the case of ice rescue systems for example may be, for example, of the order of magnitude of 0.5 m to 1.5 m, in particular in the range between 0.8 m and 1.2 m, to enable at least one rescuer to advance along the tube run. On account of the fact that, with every extended length, the tube portions leading from the tube guiding device to the head portion are filled until taut, and are consequently relatively rigid, it is possible to dispense with further devices for maintaining the distance between the tube portions, whereby the overall construction becomes relatively simple, inexpensive and functionally reliable. The region between the tube portions can accordingly be free.

In one example, the tube arrangement has a flexible sheet-like element preferably produced from water-impermeable, tension-resistant flat material, extends between the tube portions and is fastened to the tube portions. The sheet-like element stretched between the tube portions can serve as a base element of the tube run to allow safe advancement along the tube run. With the aid of the sheet-like element it is possible for any relatively small ice-free regions there may be along the tube run to be overcome without water getting between the tube portions. The upper side of the sheet-like element intended for advancement may be provided with non-slip elements or, for example, be made in a non-slip manner by means of roughening.

The sheet-like element may be an elongated web-like element which is separate from the tube portions and has on its longitudinal sides loops for the tube portions to be led through. As a result, detachable fastening of the sheet-like element to the tube portions is possible, and the sheet-like element can be pulled off the tube portions, and consequently separated from the tube arrangement (and also re-attached to it), for example, for maintenance or repair purposes, without the aid of tools.

Inflated tube portions which have become filled until taut between the head portion and the tube guiding device, and normally extend more or less parallel to one another at a mutual distance, can form a relatively stable and at the same time if need be buoyant rail system. In one example, this is used by providing a carriage which can move along the tube run and preferably has guiding devices for guiding the movement of the carriage on the tube portions. In the case of an ice rescue device, the carriage may serve, for example, as a movable base for a stretcher, with the aid of which a victim can be moved from the head portion into the safe area in the vicinity of the base element. One example of the carriage is a rolling carriage with wheels, which have a cross-sectionally concave running surface, the shape of which is adapted to the shape of the upper side of expanded tube portions in such a way that the wheels roll on the tube portions while being secured against sliding off sideways. Alternatively or additionally, guiding devices that are separate from the wheels and reliably prevent the carriage from falling off the tube run may be provided. A carriage may also be provided when the tube arrangement has only a single tube portion.

The head portion may be of a relatively stable configuration and serve as a support for various functional elements. In some examples, at least one deflecting roller is fastened to the head portion. An elongated, flexible pulling element, for example, a rope or a chain, may be led from the base element to the deflecting roller and back in the direction of the base element in such a way that an object fastened to the pulling element, for example, a carriage, can be moved between the base element and the head portion or in the opposite direction by pulling on a portion of the pulling element. With the aid of a deflecting roller, a very simple and reliably functioning transport system for movements along the extended tube run can therefore be set up.

Alternatively or additionally, other devices may also be provided on the head portion, for example, one or more gripping elements. Such gripping elements are very advantageous for the handling of the tube arrangement and, during deployment, can also easily be grasped by a victim to prevent him/her from going down under the water.

Preferably, the aid system is formed as a portable system, which can be carried quickly from a storage location to the location where it is to be deployed, for example, by two persons of average strength. Mobile variants are also possible. The base element may, for example, be fastened to a vehicle or be formed by part of the vehicle body. Integration in a water guard or fire service rescue vehicle, for example, is possible.

Some examples of the aid system are configured for use as ice rescue systems in ice rescue. However, aid systems of the types described here are not restricted to this type of use. If it is suitably designed, an aid system may also serve, for example, as a buoyant emergency bridge for overcoming expanses of water that are not too wide. For this purpose, the tubes may have to be of correspondingly large dimensions.

For some examples such as those for ice rescue, maximum extended lengths in the range from 20 to 60 meters, in particular in the range from 30 to 50 meters, are often advisable and sufficient. However, the maximum extended length of the tube run may also be longer or shorter.

In the case of rescue systems, the width of the tube run in the state in which it is deployed may be, for example, in the range of around one meter, for example of the order of magnitude of 0.5 m to 1.5 m, particularly in the range between 0.8 m and 1.2 m, to enable at least one rescuer to advance on the tube run. For other applications, greater widths may be advisable, up to widths of several meters, which possibly permit use of the extended tube run as an emergency road for motor vehicles.

These and further features emerge not only from the description and the drawings, where the individual features can be realized in each case by themselves or as a plurality in the form of subcombinations and can constitute advantageous and inherently protectable forms. Examples are illustrated in the drawings and are explained in greater detail below.

Turning now to the drawings, the obliquely perspective, schematic representation in FIG. 1 shows an example of a transportable aid system 100 in use for rescuing a person 190, who has fallen through an icy surface 193 that has formed on the surface of the water near the shore 191 of a lake 192. In such situations, rapid assistance is necessary to rescue the victim from the place where he/she has fallen in, bring him/her safely back to land and in this way save the victim from hypothermia, and consequently from dying. The aid system 100 is configured for rapid deployment in such situations and is therefore also referred to hereafter as an “ice rescue system,” “ice rescue device” or “rescue device.”

The ice rescue system has a base element 110 with a torsion-resistant frame 111, which consists essentially of welded-together or otherwise fixedly interconnected metal profiles. Examples with preferably corrosion-protected steel profiles are equally possible, as are comparatively lighter frames with aluminium profiles. The base element serves as a supporting device for an inflatable tube arrangement 120, which has two tube portions 122, 124 arranged at a mutual distance of about 80 cm to 1 m from one another and, possibly with further elements of the tube arrangement, form a tube run 125, which extends between a base portion assigned to the base element 110 and a head portion 130. The head portion is located at the free end of the tube run, which in the extended state of the tube run lies several meters away from the base element.

As can be seen in FIG. 2, the head portion 130 has a stable cross member 132 formed by two screwed-together profiles, between which the head-side ends of the tube portions 122, 124 are clamped in such a way that the tube portions are closed off in an airtight manner at the head region. The cross member serves at the same time as a spacer which keeps the tube portions at the desired lateral distance at the head end. The ends of the tube portions that are cut off here may also be connected by a further tube portion, and so the tube portions 122, 124 may in principle also be formed by two sections of a single tube.

In the case of the example of FIG. 1, the stable holding structure of the head portion is enclosed to form a round-surfaced, i.e., edgelessly delimited, stable holding structure 134. The underside of the holding structure 134 may be raised in an upwardly curved manner towards the front end in a way similar to a sleigh to make it easier for the head portion to be pushed forward on an icy surface that is possibly covered with snow or on water. Fastened to the front side of the head portion are two gripping elements 136, which on the one hand make it easier for the tube arrangement to be handled and on the other hand make it easier for a victim to securely hold the head portion, and possibly allow the victim to pull him/herself onto the tube arrangement, and consequently to safety, perhaps without outside assistance. Such grips may alternatively or additionally also be provided on the upper side and/or on the rear side of the holding structure that is facing the base part.

In the case of the example, the tube portions 124 are formed by commercially available firefighting hoses which can be rolled up flat and have a stretch-resistant outer sheath of cabled polyester fabric and an inner lining with a synthetic rubberization. In the inflated state, the tube cross section is essentially circular. Typical diameters may, for example, lie in the range from 80 mm to 120 mm. The tubes are not only watertight, but also gastight and can be filled under high gas pressures of, for example, up to 30 bar or up to 50 bar without risk of bursting. The overall length of the tube portions in the case of the example is about 30 meters; other examples have an overall length of 50 meters or more; shorter tube portions are likewise possible.

The tube arrangement includes a sheet-like element 126, which consists of flexible flat material, extends between the tube portions 122, 124 essentially over the entire length of the tube run and is fastened to the tube portions. As schematically shown in FIG. 5, formed for this purpose on the longitudinal sides of the sheet-like element are loops which are dimensioned in such a way that an expanded tube portion can comfortably be led through the loops. Being fastened by means of loops means that the sheet-like element as a whole is exchangeable and it is also possible, for example, for maintenance or repair purposes, to pull a tube portion out of its loop and thread it in again later. A waterproof-coated, tear-resistant woven fabric similar to a truck tarpaulin may be used, for example, as flat material.

The ice rescue system is structurally designed in such a way that the tube run can be extended to any desired extended length up to its maximum extended length of, for example, 30, 40 or 50 m or more entirely by compressed air being supplied in a controlled manner. Provided for this purpose, to fill the tube portions with compressed air, is a compressed gas system 150, which includes an exchangeable compressed air cylinder 152, which can be exchangeably fastened to the base element with the aid of a holder 154 fastened to the frame 111. From the compressed air outlet of the cylinder, a compressed gas line 155 leads via a reducing valve and a manually actuable shut-off valve 156 along the tube run to a compressed gas inlet 158, which is provided on the head portion 130 and, in the region of the head portion, leads into the interior of the expandable tube portions 122, 124. The schematic representation of FIG. 1 shows only a single compressed gas inlet 158, from which compressed gas channels lead to both front ends of the tube portions 122, 124. In the case of the example of FIG. 2, a separate compressed gas inlet 158A, 158B is provided for each tube portion, operated via a compressed gas line branched in the head region. It is also possible for a number of compressed gas lines to lead from the head portion to the base element.

In the case of an example with a fully extended length of 30 m or 50 m, a single compressed gas cylinder with a nominal volume of 10 liters and a filling of 200 bar is quite sufficient to fill all the expandable tube portions for fully extending and stabilizing the tube run.

As can be seen particularly well in FIG. 2, in the largely retracted state of the tube run, the spaced-apart tube portions 122, 124 of the tube run are wound up on tube storing rollers 142, 144. A dedicated tube storing roller is provided here for each tube portion. The tube storing rollers are rotatably mounted with coaxial axes of rotation on the frame 111. In the case of the example, they are supported by a common hollow shaft, which is rotatably mounted on both sides in the frame. The tube storing rollers are at approximately the same distance from one another as the tube portions in the region of the head portion, and so an intermediate space remains between the tube storing rollers. In the region of this intermediate space, the flexible sheet-like element 126 is wound up on the hollow shaft 145. Furthermore, a flexible portion of the compressed gas line is wound up here on the hollow shaft 145. A portion of the compressed gas line leads from the flange connection into a side of the hollow shaft 145 to a centrally provided tube connection, to which the flexible part of the compressed gas line is connected. These features are not represented in FIG. 2 for reasons of overall clarity.

The tube portions are guided between the tube store and the head portion 130 by a tube guiding device 160, which has for each of the two tube portions a pair of oppositely rotatable rollers 162A, 162B and 164A, 164B, respectively, which are rotatably mounted with parallel axes of rotation on the frame or on bearing elements held by the frame. The rollers have essentially cylindrical lateral surfaces and, in the case of the example, consist of a corrosion-resistant aluminium-based light metal alloy. In the region where they come closest together, the cylindrical lateral surfaces of the pairs of rollers delimit an in each case essentially parallel gap 163 and 165, respectively, which serves as a tube guiding opening for the tube portions to be guided through and is dimensioned such that the wall portions lying opposite one another of the non-expanded tube portions are pressed against one another under slight pressure in the gap such that a gastight sealing of the tube portions is obtained by the rubberized regions lying on one another on the inside of the tube. The tube portions are therefore closed off in an airtight manner on the one hand in the region of the head portion 130 and on the other hand in the region of the tube guiding opening 163 or 165 of the tube guiding device.

The function of this aid system when introducing compressed gas into the tube arrangement is now explained with reference to FIG. 3. FIG. 3A shows a schematic side view of the ice rescue system parallel to the axes of rotation of the tube storing roller 142 and the rollers 162A, 162B of the tube guiding device 160. The ice rescue system is shown with the tube arrangement almost completely withdrawn. As a result, the tube portions, largely empty of air, can be wound up flat on their respective tube storing rollers and the head portion 130 of the tube arrangement is located in the direct proximity of the rollers 162A, 162B on the tube exit side, opposite from the tube entry side, of the tube guiding device 160. The respective tube portions are clamped in place in the region of the tube guiding gap 163 formed between the rollers, and so no air can penetrate from the tube exit side (facing the head portion) to the tube entry side (facing the tube store). The shut-off valve 156 in the proximity of the compressed air cylinder 152 is still closed.

If it is then necessary for the tube run to be extended, firstly the reducing valve located on the compressed air cylinder is set to a suitable outlet pressure and then the shut-off valve is opened, so that compressed air is introduced into the tube portions 122, 124 under a predeterminable pressure from the compressed air cylinder through the compressed gas line 155 and the compressed gas inlet 158 provided on the head portion. The part of the tube portions that is located between the head portion 130 and the tube guiding device 160 is inflated until taut, to an essentially circular cross section. As a reaction to the increasing pressure inside the tube portions, the latter then attempt to increase their volume by an increasing length of tube being drawn off from the storing roller through the gap between the tube guiding rollers. As a result, the tube run laterally delimited by the inflated tube portions pushes itself of its own accord increasingly further away from the base element 110, and so the overall usable length (extended length), measured between the base element and the head portion, increases as long as compressed air continues to be introduced into the tube portions. The sheet-like element 126 held between the tube portions is likewise drawn out. Once the head portion has reached its intended position, for example the edge of the place where the victim has fallen through, the shut-off valve is closed, whereby the advancement of the head portion is ended. Since the pressurized gas between the head portion and the sealing location in the gap of the tube guiding device cannot escape in any direction, the inflated tube portions remain tautly inflated for a long time and serve as lateral stabilizations of the tube run, which can then be used by a rescuer to rescue the person who has fallen through.

Once the aid deployment has been completed, a discharge valve can be opened, so that the compressed air can escape from the inflated tube portions. This can then be wound up again onto the tube store by manually turning back the tube storing rollers. Since no sealing in the region of the tube guiding gap is necessary during this return movement, for this purpose the gap width is increased a little (for example, by a few millimeters or centimeters) using a setting device, and so, although the air is to the greatest extent forced out from the walls of the tube portions, the tube walls are not strongly pressed together.

Further optional elements of the aid system are explained on the basis of FIGS. 4 and 5. FIG. 4 shows in this respect the side view of an extended tube arrangement 120 in the proximity of the head portion 130. Fastened to the upper side of the head portion is a bearing element for a deflecting roller 170. A tension-resistant, flexible pulling element 172 in the form of a strong nylon rope leads from the base element (not represented) to the deflecting roller and from there to the front side of a carriage 180, which is schematically illustrated in a frontal view in FIG. 5. The twin-axle carriage has a flat, flexurally rigid main body in the manner of a board, on the undersides of which two axles are rotatably mounted. Fastened to the ends of the axles are running wheels 182, 184, the axle base of which corresponds essentially to the lateral distance between the tube portions 122, 124. The wheels have inwardly curved running surfaces extending concavely around them, the curved cross section of which is adapted to the largely cylindrical upper side of the inflated tube portions such that the wheels can roll along on the inflated tube portions while being secured against sliding off sideways. The tautly inflated tube portions serve in the case of this arrangement as parallel running rails, on which the carriage rolls in a guided manner similar to a rail vehicle. By pulling on one side of the pulling element, the carriage can be pulled along the tube arrangement from the base element in the direction of the head portion 130. If, on the other hand, that portion of the pulling element that is attached to the rear side of the carriage is pulled, the carriage can be pulled back from the region of the head portion in the direction of the base element. In the case of ice rescue, the carriage may serve, for example, as a stretcher for the rescued victim to bring the person in need of help quickly out of the danger zone of the place where he/she fell through to the safe zone, where first aid measures can then be initiated.

Extending the tube run takes place entirely pneumatically. The device merely requires a compressed gas source, and it is possible to dispense with electrical drive motors or drive motors operated in some other way. The structural design is extremely robust and to the greatest extent uses only commercially available components, making it relatively inexpensive to produce. The aid system is largely maintenance-free and, if a mobile compressed gas source is present, can be used virtually anywhere. The tubes should be checked for tightness at suitable time intervals, and exchanged if necessary to ensure readiness for deployment. 

1. An aid system comprising: a base element; an expandable tube arrangement comprising at least one tube portion to form a tube run extending between a base portion assigned to the base element and a head portion at a free end of the tube run; and a pressurized fluid system that fills the tube portion with pressurized fluid, wherein: (i) the tube portion is guided between a tube store and the head portion by a tube guiding device with a tube guiding opening constricting a cross section of the tube portion; and (ii) at least one pressurized fluid inlet leading into the interior of the tube portion in the region of the head portion.
 2. The aid system according to claim 1, wherein the tube arrangement comprises at least two tube portions arranged at a mutual distance from one another.
 3. The aid system according to claim 1, wherein the tube guiding device comprises a pair of oppositely rotatable rollers delimiting a gap serving as a tube guiding opening for the tube portion to be guided through, the rollers having parallel axes of rotation and being mounted on the base element.
 4. The aid system according to claim 3, further comprising a setting device that changes an axial distance between the rollers.
 5. The aid system according to claim 1, comprising a tube storing roller provided on a tube entry side of the tube guiding device that takes up the tube store.
 6. The aid system according to claim 5, wherein the tube arrangement comprises two tube portions arranged at a mutual distance from one another and a dedicated tube storing roller is provided for each of the tube portions, wherein the tube storing rollers are fitted in a substantially coaxially rotatable manner on the base part such that an intermediate space is formed between the tube storing rollers.
 7. The aid system according to claim 1, wherein the pressurized fluid system has at least one flexible pressurized fluid line leading from the base part to the pressurized fluid inlet on the head portion.
 8. The aid system according to claim 1, wherein the pressurized fluid system is a compressed gas system.
 9. The aid system according to claim 8, further comprising a mount provided on the base part that receives at least one exchangeable compressed gas containing.
 10. The aid system according to claim 1, further comprising a carriage that is moveable along the tube run.
 11. Aid system according to claim 10, wherein the tube arrangement comprises two tube portions arranged at a mutual distance from one another and the carriage comprises guiding devices that guide the movement on the tube portions.
 12. The aid system according to claim 11, wherein the guiding devices comprise wheels having a cross-sectionally concave running surface, the shape of which is adapted to a shape of an upper side of expanded tube portions such that the wheels roll on the expanded tube portions while being secured against sliding off sideways.
 13. The aid system according to claim 1, further comprising at least one deflecting roller fastened to the head portion.
 14. The aid system according to claim 13, further comprising an elongated, flexible pulling element, which is led from the base element to the deflecting roller and back in a direction of the base element such that an object fastened to the pulling element can be moved between the base element and the head portion by pulling on a portion of the pulling element.
 15. The aid system according to claim 1, further comprising at least one gripping element provided on the head portions.
 16. The aid system according to claim 2, wherein the tube arrangement has a flexible sheet-like element extending between the tube portions.
 17. The aid system according to claim 16, wherein the sheet-like element is detachably fastened to the tube portions.
 18. The aid system according to claim 16, wherein the sheet-like element is an elongated web-like element separate from the tube portions and has on its longitudinal sides loops for the tube portions to be led through.
 19. The aid system according to claim 16, wherein the sheet-like element is produced from water-impermeable, tension-resistant flat material.
 20. The aid system according to claim 1, which is configured for use in ice rescue. 